An Introduction to Buying Studio Flash Lights
Monday, 12 July 2010 16:51
Confused as to what to look for when buying your first set of studio lights? In this article, I'll run through some of the things to look for. I can't tell you exactly what to buy as everyone's needs and budgets are different, but this should give you a starting point as to help you make a more informed purchase.
Monolights or not?
There are two general "types" of studio flash-one where the flash head and controls are separate, and one where the flash unit is totally self contained (generally known as "Monolights" or “Monoblocks” ). The separate versions are handy in that the controls stay within reach, unlike with monolights where you would have to move the light, or use step ladders when you need to adjust them if the light is high up or in such a position that makes them hard to reach.
Monolights are the most commonly sold and used versions these days, and are probably cheaper due to their self contained nature, and as a result, are the type I'll deal with here (although many things are valid for both types.)
You can start with just one light and use reflectors as needed. Most people will need no more than 4, which will give you a key light (main light on the subject), fill (as its name suggests, just adds a bit of fill to remove excess shadows), a hair light and a background light- or you can use the hair and background light as both background lights in high key photos.
Expensive versus cheap
It's tempting to just buy a cheap set of lights, but it is a trade off and the old saying "you get what you pay for"does ring true. Cheap flashes can vary in colour temperature and on output slightly with each and every firing of the flash, which can mean extra work for you in post processing. There is also the obvious reliability angle.
Studio flash output is measured in watts per second, or Joules (basically the same thing). A home studio or small commercial studio will manage with lights of around 200w/s. Larger studios will mostly only need up to around 400w/s or 500w/s- you rarely need to go any higher. In fact, having too powerful a flash in too small a space will be counter productive and probably flood the space with too much uncontrollable light. More powerful lights are also more expensive (as you probably expected), and may take longer to recycle.
This is something that people tend to overlook when looking for flashes- I know I certainly did when I bought my first set of lights: How far can your flash lights be turned down? The first set I got can only be turned down to 1/5th (a fifth) of its rated power, so as they were 200w/s lights, they would only turn down to 40w/s. It may not be important if you only ever use them in a basic studio setting, but I needed to use them on location in a house to light a model sat in a window - I found I was unable to turn them down far enough to balance light on the model with the light coming in from outside.
Generally, cheaper flash units turn down to 1/8th, then mid range by 1/16th and higher end units turning down to 1/32nd - my newer 400w/s flashes turn down to 1/32nd power, so go down to 12.5w/s.
This is how quickly the flash will deliver a given quantity of light - will the flash give a brighter burst in a shorter time, or not so bright over a longer period of time (3000th of second versus 1000th of a second for example). What will you using them for? For straight forward portraits and still life, then this is not such a concern. But if you are photographing dancers in action, or even children, you may need flash units that deliver the flash in a shorter period of time to make sure that the action is frozen and that there is no motion blur.
This is the amount of time it takes for the flash to recharge before it's ready to fire again. Cheaper units tend to take longer to recharge than expensive versions - at full power, this can be up to around 3 seconds. It may not sound a lot, but when you're snapping away that can seem an eternity, and could mean you miss a shot if you are shooting something like children.
Sadly, there is no one standard accessory mount to attach accessories such as softboxes and beauty dishes. So you need to be aware as to what mount your flash unit uses and take it into consideration when buying a flash. Here in the UK, the Bowens "S-Type" mount is popular and is now probably as close to a standard that you can get, with Bowens themselves and many other manufacturers using it. There are plenty of accessories that will use this mount made by many different third party manufacturers. Elinchrom also have their own mount, and while there are plenty of accessories that fit it, there are not as many as there are for the S-Type mount, so you have less choice and they can cost more.
However, there are some accessory manufacturers who make their accessories with a universal adaptor that will allow you to use the same accessory on flashes with different mounts.
Most flash units will come with a modelling light - this is a "normal" incandescent or halogen light that is used to get an idea of how the flash will fall on the subject. It also helps illuminate the model and prevent their irises opening up too much if the studio is dimly lit.
How the light is set up to work depends upon the flash unit and it can work in one or more of these ways; straight on or off, variable power in step with flash output (the more you turn up the flash power, the modelling light gets brighter), or variable power set manually by a dial on the flash unit.
Obviously, flash units that allow you to control the modelling light manually and in step with the flash power is preferable as it gives you more control and choice.
Is it user replaceable? Many are, so you can just keep a spare and replace it yourself in the event that it should fail or gets broken. Sadly, mine are not so if it should ever fail, I have to send the flash unit off to have it replaced, meaning I will be without the flash unit for several days.
While on the subject of flash tubes - you should never touch them with your bare hands. Doing so can significantly shorten the lifespan of your flash tube!
This is a personal thing that may not affect you, but my first set of lights does not have the ability to turn off the audible beep to tell you they are charged and ready to fire again. It can annoy me after a while when you get several lights beeping away all the time, so you may want to look for lights where the "beep" can be turned off, and/or where the flash unit can make the modelling light flash off when it's ready.
All flash units will have a socket for a sync cord - this will usually be a 3.5mm jack socket, but some have the smaller 1.4mm socket (both sizes being "mono" versions of the same type you find on headphones). Studio flashes are usually sold with a sync cord to fit your flash, but they are easy and cheap enough to buy if needed. This socket can also be used to attach wireless triggers.
Most flashes also have an optical slave cell fitted (you generally only use the sync cord on one flash and fire others via the slave cells), but make sure it can be turned off if needed - I have been in a situation where other lights (from other photographers) were setting my lights off.
A few flash units now come with wireless slave triggers such as the Pocket Wizard built in, or with the option to fit a special version of the Pocket Wizard internally.
I've briefly mentioned this above, but flash output can vary between firings- either the intensity, and/or colour balance. But, you can kind of assume that more expensive lights will be more consistent, and mean less post processing.
Unfortunately you can't really tell how consistent a flash is without some real world tests - you will either have to rely on the manufacturer's blurb, or read some third party reviews, or test the lights for yourself.
Heat and cooling
This probably won't affect most people, but if you plan on doing extended periods of continuous flashes, then you should check the flash unit's duty cycle (it may be more important if you live in a hotter environment). This is how long the flash unit can be operated before you have to stop and let it cool off. Some flashes are more efficient, some use large heatsinks, and some have fans fitted to help keep them cool.
It's certainly possible to mix - or use - different brands of flash (such as Bowens and Elinchrom), but some will advocate that you don't as they will all have slightly different colour temperatures, which in turn may mean extra post processing to correct. It's not something I've encountered, but it's something to bear in mind, so you may want to choose a single brand and stick to their products.
Keep an eye out for other features - some Bowens flash units can use specially designed battery power packs, so they can easily be used on location where there is no mains power available. Certain Elinchrom models can be remotely adjusted via their Skyport wireless trigger system (by simply pressing a button on the trigger on your camera), or via a computer.
As I mentioned above, a lot will depend upon your budget, but I would try and avoid the cheapest available. Studio lights can cost a lot of money, but they are for the most part reliable and can last for many years (it's not unknown for photographers to use the same set of lights for 20+ years).
My personal “must haves” for a studio flash are; ability to turn down by at least 1/16th of its rated power, Bowens S-Type accessory mount, the ability to turn off both audible recharge beep and slave cell, and a recharge time of less than 1.5 seconds at full power.
Excerpt from Digital-Photography-School.com, original link: